TV ratings: Giants-Cowboys scores big for NBC Sunday, 'Once Upon a Time' falls some more

Fast national ratings for Sunday, Dec. 11, 2011A tight game between two marquee teams gave NBC's "Sunday Night Football" some of its best ratings of the season, carrying the Peacock to a big ratings win for the night. The NFL also boosted CBS, while ABC's "Once Upon a Time" declined again in its final episode of 2011.The Giants-Cowboys game on "SNF" helped NBC score 18.6 million viewers and an 11.3 rating/17 share in households for the night, leading CBS (13.2 million, 8.3/13) by more than 5 million viewers as things stand now (numbers for both nets will change some because of live sports in primetime). FOX averaged 6 million viewers and a 3.5/5, beating ABC's 5.9 million and 3.5/5.NBC dominated the adults 18-49 demographic with a 6.9 rating, more than doubling CBS' 3.2. FOX drew a 2.7 in the demo and ABC a 1.8....